1. Field of the Invention
The present invention relates to a semiconductor circuit device, a redundancy system, and a redundancy method thereof, and is applied to, for example, a fuse box, and the like.
2. Description of the Related Art
Heretofore, as a device for performing a redundancy operation with respect to a memory macro, there is a fuse box for retaining and transferring redundancy information (see, for example, Jpn. Pat. Appln. KOKAI Publication No. 2006-185569). The fuse box is constituted of, for example, a fuse latch circuit including a fuse and a circuit for latching fuse data, a fuse counter circuit for counting the number of transfers of fuse data, and a control circuit for controlling a signal of fuse data.
For example, a redundancy operation performed by the fuse box is started when the fuse counter circuit receives a request signal (REQ) from the control circuit in accordance with a demand signal (ACKS/D) from an external memory macro. Subsequently, upon receipt of the request signal (REQ), the control circuit acquires fuse data from the fuse latch circuit, and transfers the fuse data to the outside as fuse data (FOUTS/D). As described above, the above operation is repeated, fuse data in the fuse latch circuit is successively transferred, and when the number of transfers counted by the fuse counter circuit reaches a predetermined number, the transfer of the fuse data is terminated.
In performing the redundancy operation as described above, the conventional fuse box is configured in such a manner that unless the fuse data (FOUTS/D) is transmitted as asynchronous data, a request signal (REQ) for requesting the next fuse data cannot be operated. Thus, the conventional fuse box is configured in such a manner that the detour operation of the fuse data in which transfer of fuse data from the fuse latch circuit is performed, but transfer of fuse data (Fouts/D) from the fuse box to the outside is not performed cannot be performed. As a result of this, the conventional fuse box has a tendency to reduce the convenience.